Samsung Reveals Extent of Note7 Battery Fire Investigation

Samsung held a press conference on Monday in which it revealed the results of its internal investigation into why some of its Galaxy Note7 handsets set on fire. Last week, leaked reports confirmed the battery was to blame, but Samsung took pains today to explain the thoroughness of its investigation, which involved over 700 engineers and data gathered from testing 200,000 phones and 30,000 Note7 batteries.

In addition to enlisting the help of two independent testing labs, the Korean company built a large-scale test facility to automate different charging and discharging scenarios, which was able to replicate the failures of consumer handsets. Absolutely everything was examined, said Samsung, from hardware and software design, to manufacturing and logistics.

galaxy_note7-samsung_test_facility

Samsung's Note7 test facility.

Samsung said that two separate flaws were to blame for some batteries setting on fire in both original and replacement phones. The original Note7 battery had a design flaw in the top-right corner that was liable to short-circuit, while the batteries in replacement units were prone to combustion because of a welding defect. Some handsets were also missing insulation tape. For those interested, the company also released an infographic explaining the findings in more detail.

Going forward, Samsung said it was introducing an 8-point Battery Safety Check that includes additional inspection and testing. The firm also said it was improving training for all battery handlers across its assembly and shipping chains. In addition, it explained that more space would be allowed around the batteries in its handsets to protect them from impact-related failures, and said it would take steps to improve its battery diagnostic and controller software.

“I [hope] this serves as an opportunity to improve safety of lithium-ion not only for Samsung but for the entire industry,” Samsung mobile head DJ Koh told Recode, adding that Samsung takes responsibility for all components of the phone, including batteries made by other Samsung subsidiaries and those bought from outside companies.

Samsung confirmed that the changes would arrive in the forthcoming Galaxy S8, but told reporters not to expect its mid-cycle phone to make its usual appearance at the Mobile World Congress, held annually in February. No timeframe was given for the launch of the S8, suggesting Samsung is being careful not to put itself under undue pressure for its comeback after last year's Note7 debacle, which was said to be a result of the company trying to beat Apple's iPhone 7 to market.

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Top Rated Comments

Chicane-UK Avatar
114 months ago
Holy moly... that's a lot of phones on test! Have to admire Samsung for being so open and so thorough about this.
Score: 33 Votes (Like | Disagree)
steve62388 Avatar
114 months ago
It's good they are being pretty open about it. Not so good it happened in the first place. I wonder how many other manufacturers could have these problems?
Score: 29 Votes (Like | Disagree)
maflynn Avatar
114 months ago
I wonder if Apple would have been so open and transparent?
Doubtful - just looking at their secretive behavior.

I'm not a Galaxy fan, never owned one, but kudos to Samsung to doing the right thing, and pulling out all the stops. I think this a nice step in the right direction to rebuilding their reputation.
Score: 25 Votes (Like | Disagree)
44267547 Avatar
114 months ago
"The original Note7 battery had a design flaw in the top-right corner that was liable to short-circuit, while the batteries in replacement units were prone to combustion because of a welding defect. Some handsets were also missing insulation tape."

I think this article says it all. Samsung rushed the Note 7 and it's quality control suffered. Some of the devices for missing insulation tape is a tell tale sign this should have never happened and is unacceptable.

The biggest take away these other phone manufacturers can learn from Samsung's mistake, is to Put out a quality device, even if it means it's not going beat the other phone competitor first.
Score: 25 Votes (Like | Disagree)
kdarling Avatar
114 months ago
I think this article says it all. Samsung rushed the Note 7 and it's quality control suffered.
It doesn't mean that at all. Nobody tests phones for battery failures like this, certainly not on the scale that would've been necessary to find these relatively rare occurences ahead of time.

It only shows that mistakes happen. The key is how to address it. Samsung didn't act accordingly at first until the US government put a firmer note.

If you mean announcing a voluntary recall before the CPSC did, that's actually not unusual. Heck, Apple themselves have done the same thing before, but nobody made a big fuss over them doing it.

Holy moly... that's a lot of phones on test! Have to admire Samsung for being so open and so thorough about this.
That is definitely a lot of phones under test! Kudos for them building such a facility to figure things out.

I once helped design and build a rack to test the functionality of 100 touchscreen computers at a time, and we thought that was a lot :cool:

For comparison, remember this leaked photo of a casual iPhone 5C test rack at their factory, with just a few dozen production units under test at a time?



Attachment Image
Score: 21 Votes (Like | Disagree)
keysofanxiety Avatar
114 months ago
Holy moly... that's a lot of phones on test! Have to admire Samsung for being so open and so thorough about this.
I have to admire their balls to set up a facility like that. :D
Score: 20 Votes (Like | Disagree)